The primary character in Limbo is a nameless boy, who awakens in the middle of a forest on the "edge of hell". While seeking his missing sister, he encounters only a few human characters, who either attack him, run away, or are dead. At one point during his journey, he encounters a female character, who abruptly vanishes before he can reach her. The forest eventually gives way to a crumbling city environment. On completion of the final puzzle, the boy is thrown through a pane of glass and back into the forest. He walks a short distance until he again encounters a girl, who, upon his approach, stands up, startled. At this point, the game abruptly ends.